Monthly climate guide
Rennes weather in September
Expect warm weather in Rennes in September: afternoons reach about 22°C (72°F), while nights drop to around 11°C (52°F). Around 44 mm of rain falls over the month (fairly dry), and skies are often cloudy. Daytime highs are 2°C cooler than August and 5°C warmer than October.
What stands out in September
- Skies are at their clearest this time of year.
- It cools down fast from here: October is about 4°C cooler.
- Just 60 km apart, but Rennes runs about 2°C warmer than Saint-Malo this month.
- Only 2 months are warmer in Rennes than September.
Avg high
22°C
72°F
Avg low
11°C
52°F
Rainfall
44 mm
fairly dry
Humidity
77%
relative
Sky
55%
cloud · often cloudy
Rennes weather by month
Show the monthly averages as a table
| Month | Avg high | Avg low | Rain | Humidity | Cloud cover |
|---|---|---|---|---|---|
| January | 9°C / 48°F | 3°C / 37°F | 73 mm | 92% | 71% |
| February | 10°C / 49°F | 2°C / 36°F | 65 mm | 88% | 67% |
| March | 13°C / 55°F | 4°C / 38°F | 55 mm | 84% | 64% |
| April | 16°C / 61°F | 6°C / 42°F | 51 mm | 80% | 58% |
| May | 19°C / 66°F | 8°C / 47°F | 55 mm | 78% | 63% |
| June | 22°C / 71°F | 11°C / 53°F | 68 mm | 78% | 66% |
| July | 24°C / 76°F | 13°C / 56°F | 44 mm | 75% | 57% |
| August | 24°C / 75°F | 13°C / 56°F | 54 mm | 75% | 59% |
| September | 22°C / 72°F | 11°C / 52°F | 44 mm | 77% | 55% |
| October | 18°C / 64°F | 9°C / 48°F | 74 mm | 85% | 65% |
| November | 13°C / 55°F | 6°C / 42°F | 79 mm | 90% | 67% |
| December | 10°C / 50°F | 4°C / 40°F | 92 mm | 93% | 71% |
What to pack for September
- T-shirts plus a light layer for the evening
- Comfortable trainers or sandals for long walks
- A small travel umbrella, just in case
Is September a good time to visit Rennes?
Compare the months in the chart above to find your ideal window.
Best time to visit Rennes →Other France cities in September
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Rennes weather in September. WeatherCompare, 2026 (NASA POWER / ERA5, 2011–2020 monthly averages). https://weathercompare.eu/weather/france/rennes/september
<a href="https://weathercompare.eu/weather/france/rennes/september">Rennes weather in September</a> (WeatherCompare)
<iframe src="https://weathercompare.eu/embed/france/rennes" width="300" height="160" style="border:0;border-radius:12px" loading="lazy" title="Rennes weather in September"></iframe> <p style="font-size:12px"><a href="https://weathercompare.eu/weather/france/rennes/september">Rennes weather in September</a> – WeatherCompare</p>
Rennes in September: quick answers
Is September a good time to visit Rennes?
Yes. September is one of the best months for Rennes, with highs around 22°C and about 44 mm of rain.
How warm is Rennes in September?
Average highs are about 22°C (72°F) and average lows about 11°C (52°F), based on 10 years of daily data.
Does it rain a lot in Rennes in September?
Rennes typically gets around 44 mm of rain in September — fairly dry.
Figures are long-term averages for the area around Rennes (NASA POWER / ERA5, 2011–2020), not a forecast for a specific year. For upcoming days, see the live multi-source forecast.